Chemical Bonding: Ionic and Covalent Bonds

Lesson Objectives:

1. Students will learn about ionic and covalent bonds, and will be able to demonstrate at 80% mastery or greater knowledge of the characteristics of each type of bond.

2. Student will be able to learn what exactly both Ionic and Covalent bonds are like, and will learn qualities of both types of bonds in order to try and differentiate between the two being discussed.



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Negative Ion







Chemical Bonds:


In the natural world, atoms make up everything within us and around us. If it weren't for atoms, the world and the universe wouldn't be the way it is today. Atoms are the building blocks of all matter; however, they don't just construct into bigger and new identities and forms all by themselves. Atoms of different elements "bond" to each other to create new compounds. For example, when two hydrogen atoms bond to one oxygen atom, water, H2O, is formed. When one carbon atom bonds to two oxygen atoms, carbon dioxide is created. During chemical bonding, the exchanging and sharing of electrons is involved, and the process of handling electrons is different for each type of atomic chemical bond. There exist three different types of chemical bonds amongst atoms and elements: Ionic , Metallic, and Covalent. We will look at Metallic bonds a little later, but for now, we will only look at ionic and covalent bonds.


Ionic Bonds:

Ionic bonds are a type of chemical bond that often takes place between metals and nonmetals. There is always usually a metal in ionic bonds. Ionic bonds are formed when two or more atoms bond to each other and exchange electrons. This phenomenon is the result of different electronegeativities of atoms, or the ability of atoms to attract electrons from other neighboring/linked atoms. If the difference of the electronegativities is greater than 1.67, the bond is ionic.



There is an important rule that prevails for ionic and covalent bonds, and that is the octet rule. This rule states that atoms will obtain, shed, and share electrons until they have 8 valence electons in their outermost energy level. In the "Ionic Bonding" video, notice the amount of electrons in the outermost energy levels of the Sodium and Chlorine atoms.


Covalent Bonds:

Covalent bonds are a type of chemical bond that form between different atoms. In a covalent bond, the atoms have to "share" electrons; this is due to little or no difference in the electronegativities of the atoms.




Assignment: Please click on the links "Ionic Bonds" and "Covalent Bonds" above, and take notes. Then, in a google doc or microsoft word doc, do an internet search and give me THREE examples of an ionic compound with ionic bonds, and TWO examples of a molecular compound made form covalent bonds. (Hint: think about one compound, water, for example. What kind of elements bond to form water?) Also, please include a picture from your personal collection or from Flickr Creative Commons for ONE of the five examples. Have fun! If you need help, contact me at my e-mail.


WORTH 40 points, up to 8 pts will be rewarded for each example. Due: Monday, January 11, 2010.